posterior mediastinal node, a node in one of three groups of thoracic visceral nodes, connected to the part of the lymphatic system that serves the esophagus, pericardium, diaphragm, and convex surface of the liver. Most of the efferent vessels of the posterior mediastinal nodes end in the thoracic duct, but some join the tracheobronchial nodes. Compare thoracic visceral node.
